REGISTRATION RIGHTS AGREEMENT

Exhibit 4.5

REGISTRATION RIGHTS AGREEMENT

dated as of December 18, 2007

between

NETWORK EQUIPMENT TECHNOLOGIES, INC.

and

BEAR, STEARNS & CO. INC.,

as Initial Purchaser

This REGISTRATION RIGHTS AGREEMENT is dated as of December 18, 2007 between Network Equipment Technologies, Inc., a Delaware corporation (the “ Company ”), and Bear, Stearns & Co. Inc., as initial purchaser (the “ Initial Purchaser ”) pursuant to the Purchase Agreement dated as of December 12, 2007 (the “ Purchase Agreement ”) with the Company. In order to induce the Initial Purchaser to enter into the Purchase Agreement, the Company has agreed to provide the registration rights set forth in this Agreement. The execution of this Agreement is a condition to the closing under the Purchase Agreement.

The Company agrees with the Initial Purchaser, (i) for its benefit as Initial Purchaser and (ii) for the benefit of the beneficial owners (including the Initial Purchaser) from time to time of the Securities (as defined herein) and the beneficial owners from time to time of the Underlying Common Stock (as defined herein) issued upon conversion of the Securities (each of the foregoing a “ Holder ” and together the “ Holders ”), as follows:

Section 1 . Definitions. Capitalized terms used herein without definition shall have their respective meanings set forth in the Purchase Agreement. As used in this Agreement, the following terms shall have the following meanings:

“ Additional Filing Deadline ” has the meaning set forth in Section 2(f)(v) hereof.

“ Additional Interest Amount ” has the meaning set forth in Section 2(f) hereof.

“ Affiliate ” means with respect to any specified person, an “affiliate,” as defined in Rule 144, of such person.

“ Business Day ” means any day, except a Saturday, Sunday or legal holiday on which banking institutions in The City of New York are authorized or obligated by law or executive order to close.

“Cessation of Effectiveness Effectiveness Deadline” has the meaning set forth in Section 2(b) hereof.

“Cessation of Effectiveness Filing Deadline” has the meaning set forth in Section 2(b) hereof.

“ Common Stock ” means the shares of common stock, par value $.01 per share, of the Company, and any other shares of common stock as may constitute “Common Stock” for purposes of the Indenture, including the Underlying Common Stock.

“Company” has the meaning set forth in the preamble hereof.

“ Conversion Price ” has the meaning assigned such term in the Indenture.

“ Deferral Notice ” has the meaning set forth in Section 3(h) hereof.

“ Deferral Period ” has the meaning set forth in Section 3(h) hereof.

“ Effectiveness Period ” means the period commencing on the first date that a Shelf Registration Statement is declared effective under the Securities Act hereof and ending on the date that all Securities and the Underlying Common Stock have ceased to be Registrable Securities.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended, and the rules and regulations of the SEC promulgated thereunder.

“ Filing Deadline ” has the meaning set forth in Section 2(a) hereof.

“ Free Writing Prospectus ” has the meaning set forth in Rule 405.

“ Holder ” has the meaning set forth in the second paragraph hereof.

“ Indenture ” means the Indenture dated as of the date hereof between the Company and the Trustee, pursuant to which the Securities are being issued.

“Initial Effectiveness Deadline ” has the meaning set forth in Section 2(a) hereof.

“ Initial Purchaser ” means has the meaning set forth in the preamble hereof.

“ Interest Payment Date ” means each June 15 and December 15 of each year.

“ Issue Date ” means the first date of original issuance of the Securities.

“ Issuer Free Writing Prospectus ” has the meaning set forth in Rule 433.

“ Material Event ” has the meaning set forth in Section 3(h) hereof.

“ Notice and Questionnaire ” means a written notice delivered to the Company containing substantially the information called for by the Selling Securityholder Notice and Questionnaire attached as Annex A to the Offering Memorandum of the Company dated as of December 12, 2007 relating to the Securities.

“ Notice Holder ” means, on any date, any Holder that has delivered a Notice and Questionnaire to the Company on or prior to such date.

“Notice Holder Amendment Effectiveness Deadline ” has the meaning set forth in Section 2(e) hereof.

“ Prospectus ” means a prospectus relating to a Shelf Registration Statement, as amended or supplemented, and all materials incorporated by reference in such Prospectus.

“ Purchase Agreement ” has the meaning set forth in the preamble hereof.

“ Record Date ” means each June 1 and December 1 of each year.

“ Record Holder ” means with respect to any Interest Payment Date relating to any Securities or Underlying Common Stock as to which any Additional Interest Amount has accrued, the registered holder of such Security on the Record Date immediately preceding the Interest Payment Date.

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“ Registrable Securities ” means the Securities until such Securities have been converted into or exchanged for the Underlying Common Stock and, at all times subsequent to any such conversion, the Underlying Common Stock and any securities into or for which such Underlying Common Stock has been converted or exchanged, and any security issued with respect thereto upon any stock dividend, split or similar event until, in the case of any such security, the earliest of (i) its effective registration under the Securities Act and resale in accordance with a Shelf Registration Statement, (ii) expiration of the holding period that would be applicable thereto under Rule 144(k) (assuming all Securities are aggregated at the Issue Date and are held continuously by non-Affiliates of the Company) or (iii) its sale to the public pursuant to Rule 144 (or any similar provision then in force, but not Rule 144A) under the Securities Act.

“ Registration Default ” has the meaning set forth in Section 2(f) hereof.

“ Registration Default Period ” has the meaning set forth in Section 2(f) hereof.

“ Rule 144 ” means Rule 144 under the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the SEC.

“ Rule 144A ” means Rule 144A under the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the SEC.

“ Rule 405 ” means Rule 405 under the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the SEC.

“Rule 424 ” means Rule 424 under the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the SEC.

“Rule 433 ” means Rule 433 under the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the SEC.

“ SEC ” means the Securities and Exchange Commission.

“ Securities ” means the 3.75% Convertible Senior Notes due 2014 of the Company to be purchased pursuant to the Purchase Agreement, including any Securities purchased by the Initial Purchaser upon exercise of its option to purchase additional Securities.

“ Securities Act ” means the Securities Act of 1933, as amended, and the rules and regulations promulgated by the SEC thereunder.

“ Shelf Registration Statement ” has the meaning set forth in Section 2(a) hereof, including amendments to such registration statement, all exhibits to such registration statement and all materials incorporated by reference in such registration statement.

“ Special Counsel ” means Latham & Watkins LLP or one such other successor counsel as shall be specified by the Holders of a majority of the Registrable Securities, but which may,

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with the written consent of the Initial Purchaser (which shall not be unreasonably withheld), be another nationally recognized law firm experienced in securities law matters designated by the Company. For purposes of determining Holders of a majority of the Registrable Securities in this definition, Holders of Securities shall be deemed to be the Holders of the number of shares of Underlying Common Stock into which such Securities are or would be convertible as of the date the consent is requested.

“ Trustee ” means U.S. Bank National Association, the Trustee under the Indenture.

“ Underlying Common Stock ” means the Common Stock into which the Securities are convertible or issued upon any such conversion.

Section 2. Shelf Registration.

(a) The Company shall prepare and file or cause to be prepared and filed with the SEC, as soon as practicable but in any event by the date (the “ Filing Deadline ”) 90 days after the Issue Date, a registration statement for an offering to be made on a delayed or continuous basis pursuant to Rule 415 of the Securities Act registering the resale from time to time by Holders of the Registrable Securities (a “ Shelf Registration Statement ”). The Shelf Registration Statement shall be on Form S-3 or another appropriate form permitting registration of the Registrable Securities for resale by the Holders in accordance with the methods of distribution elected by the Holders and set forth in the Shelf Registration Statement. If the Company is eligible pursuant to Rule 430B(b) to omit from the related Prospectus the identities of selling securityholders and the amounts of securities to be registered on their behalf, the Company shall prepare and file each Shelf Registration Statement in a manner as to permit such omission and to allow for the subsequent filing of such information in a Prospectus pursuant to Rule 424(b) in the manner contemplated by Rule 430B(d). The Company shall use its reasonable best efforts to cause a Shelf Registration Statement to be declared effective under the Securities Act as promptly as is practicable but in any event by the date (the “Initial Effectiveness Deadline ”) that is 180 days after the Issue Date, and to keep a Shelf Registration Statement continuously effective under the Securities Act until the expiration of the Effectiveness Period. Each Holder that became a Notice Holder (i) within 20 days of receiving a Notice and Questionnaire from the Company or (ii) if later, prior to the filing of the initial Shelf Registration Statement shall be named as a selling securityholder in the initial Shelf Registration Statement and the related Prospectus in such a manner as to permit such Holder to deliver the Prospectus to purchasers of Registrable Securities in accordance with applicable law. None of the Company’s security holders (other than the Holders) shall have the right to include any of the Company’s securities in a Shelf Registration Statement.

(b) If a Shelf Registration Statement covering resales of the Registrable Securities ceases to be effective for any reason at any time during the Effectiveness Period (other than because all securities registered thereunder shall have been resold pursuant thereto or shall have otherwise ceased to be Registrable Securities), the Company shall use its reasonable best efforts to obtain the prompt withdrawal of any order suspending the effectiveness thereof, and in any event shall within five Business Days of such cessation of effectiveness (the “Cessation of Effectiveness Filing Deadline” ) amend the Shelf Registration Statement in a manner reasonably expected to obtain the withdrawal of the order suspending the effectiveness thereof, or file an

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additional Shelf Registration Statement so that all Registrable Securities outstanding as of the date of such filing are covered by a Shelf Registration Statement. If a new Shelf Registration Statement is filed, the Company shall use its reasonable best efforts to cause the new Shelf Registration Statement to become effective as promptly as is practicable, but in no event more than 45 days after such filing date (the “Cessation of Effectiveness Effectiveness Deadline” ) and to keep the new Shelf Registration Statement continuously effective until the end of the Effectiveness Period.

(c) The Company shall amend and supplement the Prospectus and amend the Shelf Registration Statement if required by the rules, regulations or instructions applicable to the registration form used by the Company for such Shelf Registration Statement or file a new Shelf Registration Statement, if required by the Securities Act, or any other documents necessary to name a Notice Holder as a selling securityholder pursuant to Section 2(e) below.

(d) The Company agrees that, unless it obtains the prior consent of the Holders of a majority of the Registrable Securities that are registered under the Shelf Registration Statement at such time or the consent of the managing underwriters in connection with any underwritten offering of Registrable Securities, and each Holder agrees that, unless it obtains the prior written consent of the Company and any such underwriters, it will not make any offer relating to the Securities that would constitute an Issuer Free Writing Prospectus, or that would otherwise constitute a Free Writing Prospectus required to be filed with the SEC. The Company represents that any Issuer Free Writing Prospectus prepared by it or authorized by it in writing for use by such Holder will not include any information that conflicts with the information contained in the Shelf Registration Statement or the Prospectus, and any such Issuer Free Writing Prospectus, when taken together with the information in the Shelf Registration Statement and the Prospectus, will not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(e) Each Holder may sell Registrable Securities pursuant to a Shelf Registration Statement and related Prospectus only in accordance with this Section 2(e) and Section 3(h). Each Holder wishing to sell Registrable Securities pursuant to a Shelf Registration Statement and related Prospectus shall deliver a Notice and Questionnaire to the Company prior to any intended distribution of Registrable Securities by such Holder under the Shelf Registration Statement. From and after the date the initial Shelf Registration Statement is declared effective, the Company shall, (i) in the case of a prospectus supplement, as promptly as practicable but in any event within 10 Business Days of receipt of such Notice and Questionnaire, or (ii) in the case of a post-effective amendment to the Shelf Registration Statement, an additional Shelf Registration Statement or a supplement or amendment to a document incorporated by reference in the Shelf Registration Statement, as promptly as practicable after the end of each fiscal quarter:

(i) if required by applicable law, file with the SEC a post-effective amendment to the Shelf Registration Statement or prepare and, if required by applicable law, file a supplement to the related Prospectus or a supplement or amendment to any document incorporated therein by reference or file a new Shelf Registration Statement or any other required document so that the Holder delivering such fully completed Notice and Questionnaire is named as a selling securityholder in a Shelf Registration Statement

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and the related Prospectus in such a manner as to permit such Holder to deliver such Prospectus to purchasers of the Registrable Securities in accordance with applicable law and, if the Company shall file a post-effective amendment to a Shelf Registration Statement or shall file a new Shelf Registration Statement, the Company shall use its reasonable best efforts to cause such post-effective amendment or new Shelf Registration Statement to be declared effective under the Securities Act as promptly as is practicable, but in any event by the date (the “ Notice Holder Amendment Effectiveness Deadline ”) that is 45 days after the date such post-effective amendment or new Shelf Registration Statement is required by this clause to be filed;

(ii) provide such Holder copies of any documents filed pursuant to Section 2(e)(i); and

(iii) notify such Holder as promptly as practicable after the effectiveness under the Securities Act of any new Shelf Registration Statement or post-effective amendment filed pursuant to Section 2(e)(i);

provided that if such Notice and Questionnaire is delivered during a Deferral Period, the Company shall so inform the Holder delivering such Notice and Questionnaire and shall take the actions set forth in clauses (i), (ii) and (iii) above within ten Business Days after the expiration of the Deferral Period in accordance with Section 3(h). Notwithstanding anything contained herein to the contrary, (i) the Company shall be under no obligation to name any Holder that is not a Notice Holder as a selling securityholder in any Shelf Registration Statement or related Prospectus, (ii) the Notice Holder Amendment Effectiveness Deadline shall be extended by up to ten Business Days from the expiration of a Deferral Period, and (iii) the Company shall not be under any obligation to file more than one post-effective amendment to a Shelf Registration Statement in any fiscal quarter or file a new Shelf Registration Statement if the latest existing Shelf Registration Statement was filed in the same fiscal quarter.

(f) The parties hereto agree that the Holders of Registrable Securities will suffer damages, and that it would not be feasible to ascertain the extent of such damages with precision, if:

(i) a Shelf Registration Statement has not been filed on or prior to the Filing Deadline;

(ii) a Shelf Registration Statement has not been declared effective under the Securities Act on or prior to the Initial Effectiveness Deadline;

(iii) the Company has failed to perform its obligations set forth in Section 2(e)(i) within the time period required therein (taking into account the last sentence of Section 2(e));

(iv) a new Shelf Registration Statement or a post-effective amendment to a Shelf Registration Statement filed pursuant to Section 2(e)(i) has not become effective under the Securities Act on or prior to the Notice Holder Amendment Effectiveness Deadline (taking into account the last sentence of Section 2(e));

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(v) a supplement to a Prospectus is required to be filed with the SEC pursuant to Section 2(e)(i) and fails to be filed with the SEC within the prescribed period and in the manner set forth in Section 2(e) (a date such filing is required to be made, an “ Additional Filing Deadline ”);

(vi) an amendment to the Shelf Registration Statement or an additional Shelf Registration Statement is required to be filed with the SEC pursuant to Section 2(b) and fails to be filed with the SEC within the prescribed period and in the manner set forth in Section 2(b);

(vii) An additional Shelf Registration Statement is filed with the SEC pursuant to Section 2(b) and the Company does not cause such additional Shelf Registration Statement to become or remain effective as set forth in Section 2(b);

(viii) the aggregate duration of Deferral Periods in any period exceeds the number of days permitted in respect of such period pursuant to Section 3(h) hereof; or

(ix) the number of Deferral Periods in any period exceeds the number permitted in respect of such period pursuant to Section 3(h) hereof.

Each event described in any of the foregoing clauses (i) through (ix) is individually referred to herein as a “ Registration Default .” For purposes of this Agreement, each Registration Default set forth above shall begin and end on the dates set forth in the table set forth below:

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For purposes of this Agreement, Registration Defaults shall begin on the dates set forth in the table above and shall continue until the ending dates set forth in the table above.

Commencing on (and including) any date that a Registration Default has begun and ending on (but excluding) the next date on which there are no Registration Defaults that have occurred and are continuing (a “ Registration Default Period ”), the Company shall pay to Record Holders of Registrable Securities in respect of each day in the Registration Default Period, additional interest in respect of any Security, at a rate per annum equal to 0.25% of the

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aggregate principal amount of such Security for the first 90 days of such Registration Default and a rate per annum equal to 0.50% of the aggregate principal amount of such Security thereafter (the “ Additional Interest Amount ”); provided that in the case of a Registration Default Period that is in effect solely as a result of a Registration Default of the type described in clause (iii), (iv) or (v) of the preceding paragraph, such Additional Interest Amount shall be paid only to the Holders (as set forth in the succeeding paragraph) that have delivered Notices and Questionnaires that caused the Company to incur the obligations set forth in Section 2(e) the non-performance of which is the basis of such Registration Default. Notwithstanding the foregoing, no Additional Interest Amount shall accrue as to any Registrable Security from and after the earlier of (x) the date such security is no longer a Registrable Security and (y) expiration of the Effectiveness Period. The rate of accrual of the Additional Interest Amount with respect to any period shall not exceed the rate provided for in this paragraph notwithstanding the occurrence of multiple concurrent Registration Defaults.

The Additional Interest Amount shall accrue from the first day of the applicable Registration Default Period, and shall be payable on each Interest Payment Date during the Registration Default Period (and on the Interest Payment Date next succeeding the end of the Registration Default Period if the Registration Default Period does not end on an Interest Payment Date) to the Record Holders of the Registrable Securities entitled thereto; provided that any Additional Interest Amount accrued with respect to any Security or portion thereof purchased by the Company on a repurchase date or converted into Underlying Common Stock on a conversion date prior to the Interest Payment Date, shall, in any such event, be paid instead to the Holder who submitted such Security or portion thereof for purchase or conversion on the applicable redemption date, repurchase date or conversion date, as the case may be, on such date (or promptly following the conversion date, in the case of conversion), unless the repurchase date, as the case may be, falls after the Record Date immediately preceding the Interest Payment Date and on or prior to the corresponding Interest Payment Date; and provided further , that, in the case of a Registration Default of the type described in clause (iii), (iv) or (v) of the first paragraph of this Section 2(f) such Additional Interest Amount shall be paid only to the Holders entitled thereto by check mailed to the address set forth in the Notic